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Erectile Dysfunction treatments: Viagra Connect vs Cialis Together and Eroxon

Find out how over the counter ED treatments compare and what to know before you buy
Stephanie LoweSenior writer

Erection problems are common, and some treatments are available to buy without a prescription.

Drugs such as Viagra Connect and Cialis usually come in pill form, but there are topical gels available, too – such as Eroxon  – for a drug-free alternative. 

Here, we explain how the different options work, with expert input from Which? scientist Kamisha Darroux and GP Dr Donald Grant.

Find out how you can access treatments, how they work, and what your options are – including how to get the best value when buying.


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How does Viagra work?

Viagra Connect contains the active ingredient sildenafil. It works by increasing blood flow around the body. In men, this can help with getting and maintaining an erection during sexual arousal.

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Dr Grant explains: 'Viagra works by relaxing blood vessels and blocking an enzyme that can interfere with erections. It helps men achieve and maintain an erection more easily.'

How long does Viagra last?

Viagra usually works for 4 to 6 hours, though some factors can influence that. 'You’ll get the best results around an hour after taking it,' says resident Which? scientist, Kamisha Darroux. 'But it can start working in just 30 minutes.'

Eating a heavy or fatty meal beforehand? It might take longer to kick in. Alcohol? That could reduce how well it works altogether. 

Stress and tiredness can also get in the way. Kamisha says it's recommended to take it on an empty stomach and avoid alcohol for the best results.

Erectile dysfunction drugs: what's available without a prescription?

There are two main types of erectile dysfunction drug available over the counter:

  • Viagra Connect (containing active ingredient sildenafil) 
  • Cialis Together (active ingredient: tadalafil). 

Both are available at pharmacies without a prescription, after completing a brief consultation with the pharmacist / filling out a form to check they are safe and appropriate for you to take. 

Viagra Connect vs Cialis Together vs Eroxon – what's the difference?

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Where to buy Viagra Connect and other ED drugs – and how much does it cost?

You can buy the over-the-counter versions of Viagra, Cialis and generic alternatives at pharmacies in the UK. 

Whether online or in-person, you'll need to fill out a quick questionnaire first. This is so a pharmacist can check it's safe for you to take.

If buying online, make sure you opt for a trusted pharmacy that is registered with the General Pharmaceutical Council (GPhC),

Prices are typically around £22 for a pack of 4 tablets (approx £5.50 per tablet). You can see current prices for the main branded drugs here:

Please note that we have not tested or reviewed these products, prices and retailers are listed for information only, and we aren't able to show every retailer.

Is Viagra safe?

For most people, yes. 'Over-the-counter Viagra (Viagra Connect or generic alternatives) is only available in a 50mg dose,' says Kamisha. 'It’s safe for healthy men, but people with heart issues or on certain medications should talk to a doctor or pharmacist first.' 

This is why you'll be asked to fill out a questionnaire before buying.

Viagra causes widening of blood vessels. That’s great for blood flow, but risky if you’re also taking anything that affects blood pressure, like nitrates. 'Mixing them can be dangerous,' Kamisha warns.

Natural Viagra alternatives

hand holding blue pill

Before jumping to medication, it’s worth looking at lifestyle factors that may be contributing to your erectile dysfunction issues. 

Stress, poor sleep, alcohol, and smoking can all play a role in ED. 'Persistent ED can also signal other health problems,' warns Dr Grant. “High blood pressure, diabetes, low testosterone - these are all linked.”

It's worth chatting with your GP in the first instance, rather than reaching for the pills, to rule out anything else.

How common is erectile dysfunction?

Erectile dysfunction is an incredibly common condition that can affect men of any age.

Despite this, there is a stigma that can cause men to mask the condition and avoid coming forward for treatment or advice. But persistent erectile dysfunction can indicate various underlying health conditions. 

Dr Grant tells us; 'As ED is linked so closely to blood flow, it can be a massive indicator of cardiovascular issues, such as high blood pressure, high cholesterol or diabetes.

Low testosterone levels can impact men’s ability to maintain an erection while also dramatically reducing libido. If ED is occurring often or slowly getting worse, I strongly advise men to seek an open and honest conversation with their GP, who can advise further on tailored treatment options.'

You can find out more about erectile dysfunction, including possible causes and treatment options, on the NHS website.

Viagra side effects and how to deal with them

man laying in bed

Most side effects are mild, such as headaches, nausea, or a stuffy nose. But if you feel dizzy or your erection lasts longer than four hours (yes, it happens), you should seek help right away. 

It’s not addictive, but if you feel like you’re relying on it without dealing with the root cause, it’s time to check in with your GP.

Can women take Viagra?

No, Viagra isn’t approved for use in women.


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Meet our experts

For our guide to erectile dysfunction drugs, we worked with our in-house scientist and sought advice from a GP, as well as researching the products available, your most searched-for questions, and checking prices. Our experts for this guide were:

Kamisha Darroux, Principal Scientific Adviser at Which?

Kamisha Darroux, Which?

Kamisha has a BSc in Pharmacology and a passion for skincare. She has been part of the Which? in-house science team since 2017. In her capacity as scientific adviser Kamisha has worked across a huge range of projects covering everything from product safety investigations to face mask testing and analysis.

Dr Donald Grant, GP and Senior Clinical Advisor at The Independent Pharmacy

Dr Grant qualified as a Doctor in Bristol in 1985. He has wide clinical experience as a GP in and around Bristol. 

He is the senior clinician at The Independent Pharmacy.